This invention relates to driver circuits for a plurality of gas discharge lamps.
In a typical prior art driver circuit for a plurality of gas discharge lamps the lamps are driven in series directly by a voltage developed across the secondary winding of a transformer. The voltage developed across the transformer secondary winding must be high enough to cause all of the lamps to strike when the circuit is powered on. However, setting the voltage developed across the transformer secondary winding at an otherwise desirable high level may contravene safety requirements and may increase operating stress on the circuit's switching components to an unacceptable degree.
It is known to connect to the lamps capacitors which act as starting aids, in order to increase the pre-strike voltage applied to the lamps. However, for driving three or more series-connected lamps, such capacitor starting aid configurations may still have to generate secondary winding voltages which are close to or exceed safety limits.